The advent of the Internet has created new distribution avenues for the communication of digital media such as music, video and still graphics. It has also created an underground network of media pirates. No sooner does a digital work become available for purchase then it becomes available illegally on peer to peer networks. In some cases intellectual property is leaked prior to its official release and made available to an increasingly tech-savvy populace.
As copyright holders have worked within the legal system to protect their interests, networks of media pirates have developed more sophisticated techniques. Such techniques have made theft more widespread and difficult to prosecute. Despite the existence of legitimate avenues for digital distribution (such as iTunes), a significant amount of media downloads are pirated.
Recently, digital watermarking and steganography have been proposed as an effective enforcement mechanism. The aim of digital watermarking is to use information hiding techniques to create an unobtrusive yet robust means to embed ownership information in media that may be subject to unauthorized distribution. In this manner, the media can be located and media pirates can be prosecuted. This is especially relevant during the production phase of new media, where an unauthorized leak can create substantial losses for a movie studio.
For a digital watermark to be considered effective in some embodiments, it needs to meet the following criteria: it must be unobtrusive, robust to intentional and unintentional attempts at removal, and have sufficient capacity for unique watermarks. Creating a watermark that meets these requirements for some embodiments has proven elusive. For instance, previous methods have sought to embed information into coefficients of the frequency domain or the wavelet domain, but there is no guarantee that the embedded regions are critical to the file's integrity.